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<\/p>\nScientists equipped with soil vapor detection equipment and ground radar were at the home of the mother of Kristin Smart\u2019s convicted killer for a second day, scanning the ground for secrets in the dirt 30 years after she vanished.<\/p>\n
On Thursday, soil engineer Tim Nelligan and former FBI chemist Brian Eckenrode, assisted by local soil scientist Steve Hoyt, placed probes into the ground near Susan Flores\u2019 property in the heart of Arroyo Grande. They were joined by a team of ground radar experts who scanned the heavily concreted property, assisting the San Luis Obispo County sheriff with serving a search warrant at the home.<\/p>\n
\u201cWe\u2019re rooting around for answers,\u201d Nelligan said, \u201cWe all want to bring Denise and Stan Smart some peace after all these years.\u201d <\/p>\n
Susan Flores\u2019 son, Paul Flores, was the last person seen with Smart as the two walked toward her dormitory at Cal Poly San Luis Obispo after a 1996 Memorial Day party. She was eventually declared dead, but her remains have never been found.<\/p>\n
Decades passed before Flores was arrested and tried. He was sentenced to 25 years to life in prison three years ago for Smart\u2019s murder. But, insisting on his innocence, he has never provided a location for her remains.<\/p>\n
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Kristin Smart disappeared nearly 30 years ago, in May 1996.<\/p>\n
(The Record via Tribune News Service)<\/p>\n
Three years ago, Nelligan and his colleagues, working from the backyard of a neighbor of Susan Flores, used soil vapor sampling to detect volatile organic compounds they say may be associated with decomposing human remains. Nelligan, an environmental engineer from San Clemente, met Smart in college. He recalls her knocking on his door and asking to use his landline phone.<\/p>\n
Nelligan was out in that yard again this week. He pushed a small tool known as a soil vapor probe, with a long, straw-like attachment, about three to five feet into the earth. Any gases the probe encounters are vacuumed in and collected, then sealed in a canister. The extracted volatile organic compounds can then be sent for analysis.<\/p>\n
Nelligan said that, since 2023, they had refined the science and were preparing to publish an academic paper on groundbreaking body detection methods in soil.<\/p>\n
In September 2023, they helped federal investigators in Yakima, Wash., locate two bodies, said Tim Perry, a former federal prosecutor and top Department of Homeland Security official. One of the bodies, that of a pregnant woman, was found just 10 feet from where their probes suggested human remains lay as they worked with Homeland Security Investigations, according to Nelligan.<\/p>\n
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Tim Nelligan drops off soil vapor samples taken from the backyard of a neighbor of Susan Flores to a lab in 2023.<\/p>\n
(Brian Eckenrode)<\/p>\n
Since then, they have worked with control samples and real bodies buried in soil at a body farm to refine their methods further. Some of the work led to Wednesday\u2019s search warrant for the property in the 500 block of East Branch Street in Arroyo Grande. <\/p>\n
Sheriff Ian Parkinson, along with investigators and the experts, appeared at the home on Wednesday morning shortly after a detective served a search warrant to Flores.<\/p>\n
\u201cThis investigation is related to the Kristin Smart disappearance,\u201d the Sheriff\u2019s Office said in a statement. \u201cThis activity is the result of a search warrant signed by a Superior Court judge. The Sheriff\u2019s Office remains committed to bringing Kristin home to her family.\u201d<\/p>\n
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